title: Valsalva manoeuvre can be used to study baroreflex sensitivity in pregnancy.
abstract: OBJECTIVE
  The aim of this study was to assess whether baroreflex sensitivity can be measured in a non-invasive manner with the Valsalva manoeuvre in pregnancy.
  
  
  METHODS
  Baroreflex sensitivity was measured from the reflex response to phenylephrine injection and phase four of the Valsalva manoeuvre in nine pregnant women at 27 (range 24-33) gestational weeks.
  
  
  RESULTS
  Both the phenylephrine test and the Valsalva manoeuvre yielded similar estimates of baroreflex sensitivity (9.3 (4.1) ms/mmHg vs. 8.0 (5.2) ms/mmHg, Pearson's correlation coefficient r = 0.81, P < 0.008, linear regression BRSValsalva (ms/mmHg) = 1.03 x BRSPhenylephrine + 1.59). Comparable changes in heart rate and blood pressure were obtained with the phenylephrine test and the Valsalva manoeuvre.
  
  
  CONCLUSIONS
  The physiological challenge caused by the Valsalva manoeuvre can be used to measure baroreflex sensitivity in pregnancy. A possibility to study baroreflex function non-invasively, without pharmacological intervention, benefits future research of blood pressure regulation in pregnancy.
authors.affiliation: Department of Obstetrics and Gynecology, University of Turku, Finland. eeva.ekholma@tyks.fi
authors.forename: E M
authors.initials: EM
authors.lastname: Ekholm
authors.forename: R K
authors.initials: RK
authors.lastname: Vesalainen
authors.forename: K U
authors.initials: KU
authors.lastname: Tahvanainen
authors.forename: T
authors.initials: T
authors.lastname: Kaila
authors.forename: R U
authors.initials: RU
authors.lastname: Erkkola
mesh_terms: D000328:Adult; D017704:Baroreflex / Q000502:physiology*; D001794:Blood Pressure; D005260:Female; D006339:Heart Rate; D006801:Humans; D010656:Phenylephrine; D011247:Pregnancy / Q000502:physiology*; D014636:Valsalva Maneuver; D014662:Vasoconstrictor Agents
chemical_list: D014662:Vasoconstrictor Agents; D010656:Phenylephrine